Pressure vessel for compressed gases utilizing a replaceable and flexible liner

Abstract

A pressure vessel assembly, and method of use, for storing a gas at an elevated pressure. The assembly includes a vessel body having a rigid wall with an inner surface defining a storage chamber and with an inlet allowing the gas to enter the storage chamber. The assembly includes a flexible liner positioned within the storage chamber to be in fluid communication with the inlet to receive any fluid entering the vessel body. The liner is formed of an elastic inner layer contacting the gas and a metallic outer surface. The inflated, unrestrained liner volume is generally at least as large as the chamber volume and more typically, slightly larger. Stored gas contacts the inner surface of the liner and expands the liner from a smaller deflated volume until the outer surface of the liner contacts the wall of the pressure vessel.

1. An apparatus for storing a fluid, comprising:
 a vessel body including rigid walls with inner surfaces defining a chamber for storing the fluid and including an inlet for allowing a fluid to enter the chamber; and 
 a liner formed of flexible material positioned within the chamber and connected to the inlet to receive the fluid entering the chamber, wherein the fluid received by the liner contacts an inner surface of the liner and forces the liner to expand until an outer surface of the liner contacts the inner surfaces of vessel body, whereby the vessel body provides resistive forces to contain the fluid; 
 wherein the liner comprises a contiguous sheet with the inner surface on a first side and the outer surface on a second side and wherein the inner surface of the sheet defines an inner volume of the liner, the inner volume in an unrestrained and inflated state being greater than about a volume of the vessel body chamber; 
 wherein the sheet is formed of a first layer including the inner surface formed of elastic material end a second layer abutting the first layer including the outer surface formed of material with low permeability to at least one gas; and 
 wherein the second layer material comprises a metallic foil. 
 
   
   
     2. The apparatus of  claim 1 , wherein the fluid is a gas at an elevated pressure relative to a pressure exterior to the vessel body. 
   
   
     3. The apparatus of  claim 1 , wherein metallic foil is formed from a metal selected from the group consisting of aluminum, nickel, titanium, tungsten, and gold. 
   
   
     4. The apparatus of  claim 1 , further including a valve connected to the vessel body inlet at the connection between the inlet and the liner, wherein the liner includes a stem formed of elastic material positioned between the inlet and the valve, whereby a hermetic seal is obtained between the valve, the inlet, and the liner. 
   
   
     5. A pressure vessel for storing compressed gases, comprising:
 a vessel body including a rigid wall enclosing an inner chamber and an inlet providing a passage to the inner chamber; 
 a valve assembly including a fitting connecting the valve assembly to the inlet of the vessel body; and 
 a liner insert with a contiguous wall and stem having an inner surface and an outer surface, the liner insert being positioned within the inner chamber with the stem being interposed between the valve fitting and an inner surface of the inlet of the vessel body, and wherein the liner insert wall comprises a flexible material and the inner surface defines a deflated volume and an inflated volume, the deflated volume being less than a volume of the inner chamber and the inflated volume being at least as great as the volume of the inner chamber; 
 wherein the wall of the liner insert comprises a layer of elastic material including the inner surface and a layer of metallic material including the outer surface. 
 
   
   
     6. The pressure vessel of  claim 5 , wherein layer of metallic material is applied to the elastic layer using metalization and comprises a metal, or an alloy including a metal, selected from the group consisting of aluminum, nickel, titanium, tungsten, and gold. 
   
   
     7. The pressure vessel of  claim 5 , wherein the rigid wall is contiguous to form a cylinder and wherein the liner insert has a shape defined by the outer surfaces when the liner insert is inflated in an unrestrained state that is generally cylindrical, the diameter of the liner insert cylinder being greater than about the diameter of the rigid wall cylinder.